Aftermarket head unit for Scion xB

yes, you can get the steering wheel contorls back, and it will cost you a little more. Pac-audio.com has the pioneer interface as well as a universal interface to retain steering wheel controls. 

ok. I already got that, so only problem now is aux input in the dash. Is there any way I can make it work too????

The new deck will likely have one of it's own you can use. I'm not sure what this factory aux-in looks like, but you may be able to either wire into it (if it's a simple phono jack), or put another in it's place on the dash. The aux in on the new unit will likely use rca connections, but you can run an rca cable, with an adapter to go on the end of it to whereever you need it.My ex once told me I have a perfect face for radio.